Effects of flunixin meglumine on postponement of ovulation in mares.

This research delves into the use of flunixin meglumine in delaying ovulation in mares. However, the findings indicate that the drug had no significant impact in postponing ovulation nor in affecting mare fertility, uterine edema, or serum progesterone concentrations.

Research Objectives

• The study primarily aimed to determine the efficacy of flunixin meglumine as a treatment to delay ovulation in mares. This is significant in the context of horse breeding, where controlling the timing of ovulation can be beneficial.
• Secondary objectives included assessing mare fertility following the administration of flunixin meglumine during their estrous cycles, and evaluating the effects of this drug on the function of the corpus luteum post-ovulation.

Research Methodology

• The research conducted was a single-blinded, placebo-controlled, crossover study involving 13 healthy mares. This design is used to minimize the effects of confounding variables and bias, thereby increasing the robustness of the findings.
• The mares were administered either flunixin meglumine or a placebo solution and then artificially inseminated. The number of days until ovulation, uterine edema score, and pregnancy were then tracked via ultrasonography.
• Serum progesterone concentrations were assessed at 5 and 12 days after ovulation using a radioimmunoassay, an in-vitro assay technique used to measure concentrations of hormones in the body.

Research Findings

• The results were compiled from 45 estrus cycles of the 13 mares. Findings showed that the number of days to ovulation from the initial detection of a follicle greater than or equal to 30mm was not significantly affected by the administration of flunixin meglumine compared to the placebo.
• Similarly, the per-cycle pregnancy rate showed no significant difference between flunixin meglumine and the placebo groups. Likewise, the drug did not significantly affect behavioral signs of estrus, uterine edema, or serum progesterone concentrations.

Research Conclusions

• The research concluded that flunixin meglumine is not effective in postponing ovulation in mares.
• The secondary findings demonstrated that the drug does not affect mare fertility, uterine health, or hormone levels, specifically serum progesterone.
• These findings are important for future approaches to managing breeding cycles in mares, as it establishes that flunixin meglumine may not be a viable option for delaying ovulation.